a) Field of the Invention
The invention is directed to a closure for mounting in an opening in a thin wall such as a sheet metal cabinet door, a sheet metal cabinet flap, a sheet metal cabinet housing wall or the like with an elongated, substantially cup-shaped housing whose edge passes into a flange and which has, at one end, a bearing support for an actuation lever and, at the other end, a lock device for the actuation lever in its position in which it is swiveled into the housing, and a fastening device which clamps the thin wall between itself and the flange.
b) Description of the Related Art
A closure of the type mentioned above is already known from EP 0054225 A1 and also, for example, from U.S. Pat. No. 5,267,762. Further, reference is had to U.S. Pat. No. 4,693,503 and to brochure F-4 published by Southco, Inc., Concordville, Pa., USA, entitled “Adjustable Lever Latch”.
The closures shown in the U.S. references are simple clamping closures and are locked by a clamping block which lies behind a surface formed by the door frame, housing frame or the like as a result of the pivoting movement of the actuation lever around an axis parallel to the wall surface or door leaf surface and accordingly achieves the locking effect. This means that the closure must always be arranged with its longitudinal extension perpendicular to the wall edge as is shown, for example, in FIG. 1 of U.S. Pat. No. 4,693,503. A further disadvantage consists in that the handling part of the pivoting handle must be pivotable by a relatively large angle, e.g., greater than 60°, so that the pressing surface formed by the other end of the lever is swiveled away sufficiently far so as not to impede the opening of the door.
On the other hand, this necessarily large pivoting angle requires sufficient space between the edge of the housing and the edge of the lever in the area of the swiveling axis to allow this edge to be tucked away inside. This space also remains clearly visible when the lever is folded in, is visually unappealing and can collect dirt or the like.
This relatively wide gap which is formed between the housing and pivoting lever and which is substantially conical in cross section is clearly shown in the top view shown in the brochure.
Another disadvantage of the device known from the U.S. references is that the closure automatically springs up when not sufficiently secured in its folded-in position due to outwardly directed spring forces, e.g., due to vibratory loading, and the closure therefore opens in an unwanted manner. The closure according to EP 0054225 does not have this disadvantage.
Another disadvantage shared by all of the references consists in that the closure can not be mounted blindly, i.e., the two sides of the thin wall in which the closure is to be mounted in a corresponding opening must be accessible; specifically, one side must be accessible for the insertion of the cup-shaped housing until the flange contacts the edges of the opening in the thin wall, and the other side must be accessible for screwing on union nuts or screw caps (EP 0054225) or for arranging a clamping clip in order to bring the clip into a clamping contact with the edge surface of the thin wall by means of a clamping screw whose head is likewise accessible on this side (U.S. patents).